Analysis of Perception of Motion in Television Signals and its Application to Bandwidth Compression

The method and results are reported of subjective assessment tests on the perception of motion in television signals. Discussed are applications of these results to the transmission technique for the difference between two adjacent frame signals. The main results are as follows. 1) Smoothness of motion is lost by field-repeating or frame-repeating TV signals, unless motion is slow. The just perceptible velocity and acceptable limit of velocity are determined by subjective tests. The velocity of moving objects should be very low in order to obtain smooth motion. 2) The precision required in separating the standard television signal into stationary and moving parts is derived from the just perceptible velocity in 1). It is about 1/3 of a Nyquist interval; that is, equivalent to a viewing angle of 45 s, when the viewing distance is 4 × (height of picture). 3) The apparent Gaussian noise level increases by 1 ∼ 3 dB when television pictures are field-repeated. On the other hand, it decreases in frame-repeated pictures, provided that the number of repetitions is small. 4) From subjective assessment of the degradation of picture quality caused by blurring of the moving part, it becomes clear that the bandwidth of the signal of the moving part can readily be reduced by a factor of 3.5.